JP2017151271A - Lens barrel and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens barrel and optical instrument that prevent movement members in the lens barrel from being loose, and achieve miniaturization and reduction in weight.SOLUTION: A lens barrel includes: a first lens cylinder (a first movement member) 3 that is disposed so as to overlap in a radial direction of a lens barrel, and is moved in an optical axis direction of the lens barrel; and a second lens cylinder (a second movement member) 4, and the lens barrel comprises an extension spring (urging means) 7 that is interposed between the first lens cylinder 3 and the second lens cylinder 4 to relatively urge both lens cylinders 3 and 4 in the optical axis direction, in which the extension spring 7 is interiorly provided in an area in each radial direction of the first lens cylinder 3 and the second lens cylinder 4, that is, in spring reception grooves 32 and 42 provided in each of cylinders 3 and 4.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a technique for eliminating backlash (moving gap) in a moving direction between a first member and a second member that are mounted in a lens barrel and relatively moved, and further, the first member and the second member have a diameter of the lens barrel. The present invention relates to a lens barrel and an optical device that realize a reduction in diameter of lens barrels arranged in a direction.

  In a lens barrel of an imaging apparatus including a camera, a member such as a lens frame that holds a lens, a lens group, and the like is moved in the optical axis direction within the lens barrel in order to perform zooming and focusing. Conventionally, a cam mechanism has been used as a structure for moving this member, and a cam pin provided on the moving member is engaged with a cam groove provided on a cam cylinder that is rotated around the optical axis of the lens barrel. I am letting. In this cam mechanism, when the cam cylinder is rotated, the cam pin is moved along the cam groove, and the moving member is moved in the optical axis direction together with the cam pin.

In this cam mechanism, a predetermined gap is provided between the cam pin and the cam groove so that the cam pin is smoothly moved in the cam groove. Therefore, this gap becomes the backlash of the cam pin relative to the cam groove, and the backlash of the moving member provided with the cam pin. Due to the play, the position of the lens group holding the moving member in the optical axis direction is not stable, and the optical performance of the lens mirror is degraded.

  In order to eliminate such backlash in the cam mechanism, Patent Document 1 provides a one-sided member that is different from the moving member that holds the lens, and a one-sided pin provided on the one-sided member and a moving member. A technique for urging a provided cam pin in the direction around the optical axis has been proposed. According to this technique, the cam pin and the moving member are urged in one direction around the optical axis by the one-sided member, and the cam pin comes into contact with the cam groove in the one direction. Can be prevented.

  Further, in Patent Document 2, a biasing member (a tension spring) is hung between pins provided on a front cylinder and a middle cylinder which are moved by a cam mechanism in the optical axis direction of the lens barrel. There has been proposed a structure in which the cam pins of the front cylinder and the middle cylinder are respectively brought into contact with the cam grooves by the urging force. According to this technique, it is possible to prevent backlash in each of the front cylinder and the middle cylinder.

JP 2010-66633 A JP 2001-174686 A

  The technique of Patent Document 1 needs to provide a biasing member and an urging member in addition to the moving member, which increases the number of components of the lens barrel and is disadvantageous for reducing the weight of the lens barrel. In addition, it is necessary to secure a space for disposing the biasing member in the lens barrel, which is disadvantageous for downsizing the lens barrel.

  Since the technology of Patent Document 2 can prevent backlash between the front cylinder and the middle cylinder that are built in the lens barrel, a separate member such as the one-sided member of Patent Document 1 is unnecessary, and the number of parts is reduced. This is advantageous. However, in order to dispose the urging member in the lens barrel, it is necessary to secure a space for disposition between the front barrel and the middle barrel in the radial direction, and the diameter dimension of the lens barrel is increased accordingly. This is disadvantageous for downsizing the lens barrel.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lens barrel and an optical apparatus that prevent the moving member from rattling in the lens barrel and that are reduced in size and weight.

  A first aspect of the present invention is a lens barrel provided with a first moving member and a second moving member that are arranged so as to overlap in the radial direction of the lens barrel and are moved in the optical axis direction of the lens barrel. And an urging means that is interposed between the first moving member and the second moving member and urges both members in the optical axis direction. The urging means includes the first moving member and the second moving member. Two moving members are disposed in the radial region.

  According to a second aspect of the present invention, there is provided a fixed barrel of the lens barrel, and a first movable barrel disposed so as to overlap the fixed barrel in the radial direction of the lens barrel and moved in the optical axis direction of the lens barrel. A lens barrel including a first moving member and a second moving member, and provided with an urging means interposed between the first moving member and the second moving member to urge both members in the optical axis direction. The urging means is disposed in a radial region where the fixed cylinder and the moving member adjacent to the fixed cylinder among the first moving member and the second moving member are present.

  According to a third aspect of the present invention, there is provided a cam barrel that is rotated, a first lens barrel that supports a first lens group that is cam-engaged with the cam barrel and moves in the optical axis direction, and a cam that is engaged with the cam barrel. In combination, the second lens cylinder that supports the second lens group that is moved in the optical axis direction independently of the first lens cylinder, and the first lens cylinder and the second lens cylinder are interposed between the two. An urging means for urging the lens cylinder in the optical axis direction is provided, and a storage groove for accommodating the urging means is formed in at least one of the first lens cylinder and the second lens cylinder.

  The present invention is further configured as an optical apparatus such as a camera, an interchangeable lens, a telescope, a binocular, and a projector provided with the lens barrel of the first to third inventions.

  According to the present invention, since the first moving member and the second moving member are respectively urged in the optical axis direction by the urging means, the positions of the first moving member and the second moving member in the optical axis direction are stabilized. The optical performance of the lens barrel can be prevented from being lowered, and high focusing accuracy can be obtained. Since the urging means is disposed in the radial region of the first moving member, the second moving member, and the fixed member, even if the urging means is housed in the lens barrel, The diameter of the lens barrel is not increased and the diameter of the lens barrel can be reduced.

FIG. 3 is a cross-sectional view including a cam pin of the lens barrel of the first embodiment. FIG. 3 is a partial exploded perspective view of a main part of the lens barrel of the first embodiment. (A) is the top view which looked at the 1st lens cylinder of the lens barrel of Embodiment 1 from the outer diameter direction, (b) is the 1st lens cylinder and 2nd along the BB line of the same figure (a). Sectional drawing of a lens cylinder. (A) is the top view which looked at the 1st lens cylinder of the lens barrel of the modification 1 of Embodiment 1 from the outer-diameter direction, (b) is sectional drawing of a lens barrel. (A) is the top view which looked at the 1st lens barrel of the lens barrel of the modification 2 of Embodiment 1 from the outer-diameter direction, (b) is sectional drawing of a lens barrel. (A) is the top view which looked at the 1st lens cylinder of the lens barrel of the modification 3 of Embodiment 1 from the outer-diameter direction, (b) is sectional drawing of a lens barrel. (A) is the top view which looked at the 1st lens cylinder of the lens barrel of Embodiment 2 from the outer diameter direction, (b) is sectional drawing of the 1st lens cylinder and 2nd lens cylinder which comprise the lens barrel. . (A) is the top view which looked at the 1st lens cylinder of the lens barrel of Embodiment 3 from the outer diameter direction, (b) is sectional drawing of the 1st lens cylinder and 2nd lens cylinder which comprise the lens barrel. .

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial cross-sectional view of a lens barrel of Embodiment 1 of the present invention. This lens barrel is configured as a focusable lens barrel including the first lens group and the second lens groups L1 and L2.

  FIG. 1 is a cross-sectional view including a cam pin, which will be described later, and the lens barrel has a fixed barrel 1 that is fixed to a simplified camera body or detachable by a lens mount. A cam cylinder 2 is supported on the outer periphery of the fixed cylinder 1 so as to be rotatable around a cylinder axis. The cam cylinder 2 is integrally provided with a focus operation ring for performing focusing (focusing) (not shown). When the photographer manually rotates the focus operation ring, the cam cylinder 2 is integrally rotated. In the case of autofocus, the cam cylinder 2 is rotated by a motor.

  A first lens cylinder 3 positioned on the outer peripheral side and a second lens cylinder 4 positioned on the inner peripheral side are fitted in the inner periphery of the fixed cylinder 1 in a concentric state. A first lens group L1 composed of four lenses is supported by a first lens frame 5 in the front end portion of the first lens tube 3. A second lens group L2 composed of two lenses is supported by the second lens frame 6 in the front end portion of the second lens cylinder 4. The first lens cylinder 3 and the first lens frame 5 are first moving members in the present invention, and the second lens cylinder 4 and the second lens frame 6 are second moving members in the present invention.

  FIG. 2 is an exploded perspective view of a part of the lens barrel. 1 and 2, the inner peripheral side region of the cam barrel 2 of the fixed barrel 1 penetrates in the radial direction of the lens barrel (hereinafter, the radial direction is the radial direction of the lens barrel), and the optical axis direction A guide groove 11 made of a linear groove extending in the direction of the lens barrel is formed. On the other hand, a first cam groove 21 and a second cam groove 22 each having a required shape are formed in the cam cylinder 2 in a region intersecting with the guide groove 11. The first cam groove 21 and the second cam groove 22 may be either an open groove penetrating in the radial direction of the cam cylinder 2 or a concave groove provided on the inner peripheral surface side. Has been.

  On the outer peripheral surface of the first lens barrel 3, a first cam pin 31 penetrating the guide groove 11 in the radial direction is erected in the outer radial direction, and the outer diameter side end portion of the first cam pin 31 is The first cam groove 21 is engaged with the first cam groove 21. On the outer peripheral surface of the second lens cylinder 4, a second cam pin 41 that penetrates the clearance groove 30 opened in the first lens cylinder 3 and further penetrates the guide groove 1 in the radial direction stands up in the outer diameter direction. An end portion on the outer diameter side of the second cam pin 41 is engaged with the second cam groove 22 in an inserted state.

  The guide groove 11, the first cam groove 21, the second cam groove 22, the first cam pin 31, and the second cam pin 41 are equally arranged at three locations in the circumferential direction. Only the configuration is shown.

  With this configuration, when the photographer rotates the focus operation ring described above, the cam cylinder 2 integrated therewith is rotated. Accordingly, the first cam pin 31 engaged with the first cam groove 21 is moved in the optical axis direction following the cam groove shape of the first cam groove 21 while the rotation around the optical axis is restricted by the guide groove 11. The first lens cylinder 3 in which the first cam pin 31 is erected, that is, the first lens unit L1 is moved in the optical axis direction.

  Similarly, the rotation of the cam cylinder 2 causes the second cam pin 41 engaged with the second cam groove 22 to follow the shape of the second cam groove 22 while the rotation around the optical axis is restricted by the guide groove 11. The second lens cylinder 4 that is moved in the axial direction and has the second cam pin 41 standing up, that is, the second lens unit L2 is moved in the optical axis direction. The first lens group L1 and the second lens group L2 are moved in the optical axis direction, thereby realizing focusing in the lens barrel.

  FIG. 3A is a plan view of a part of the first lens cylinder 3 viewed from the outer diameter direction, and FIG. 3B is a cross-sectional view of a portion corresponding to the line BB. 2 and 3, a region where the first lens cylinder 3 and the second lens cylinder 4 overlap in the radial direction, that is, a circumference where the guide groove 11, the first cam pin 31, and the second cam pin 32 are not provided. In the directional region, a spring housing groove is formed, which is an opening groove that penetrates in the radial direction. The first lens barrel 3 is formed with a first spring housing groove 32 made of a straight groove along the optical axis direction as an opening groove penetrating in the radial direction, and the second lens cylinder 4 is a straight line along the optical axis direction. A second spring housing groove 42 made of a groove is formed as an opening groove penetrating in the radial direction.

  The first spring storage groove 32 and the second spring storage groove 42 are formed in a state where partial regions in the optical axis direction overlap each other in the radial direction. Here, the region on the front side (the subject side of the lens barrel) of the first spring housing groove 32 and the region on the rear side (the camera body side of the lens barrel) of the second spring housing groove 42 are in a required length region. They are stacked in the radial direction.

  A first spring support pin 33 is erected on the inner peripheral surface of the first lens cylinder 3 at a position rearward of the first spring housing groove 32. The first spring support pin 33 is constituted by a screw (small screw) screwed into the first lens cylinder 3 from the inner diameter direction, and is arranged in the groove of the second spring accommodating groove 42 of the second lens cylinder 4. It is installed. On the other hand, a second spring support pin 43 is erected on the outer peripheral surface of the second lens cylinder 4 at a position in front of the second spring housing groove 42. The second spring support pin 43 is constituted by a screw screwed into the second lens tube 4 from the outer diameter direction, and is disposed in the groove of the first spring housing groove 32 of the first lens tube 3. Yes.

  A coil spring 7 is connected between the first spring support pin 33 and the second spring support pin 43 along the optical axis direction. Here, a tension spring is disposed as the coil spring 7, a front end portion of the tension spring is hooked on the second spring support pin 43, and a rear end portion is hooked on the first spring support pin 33. .

  The tension spring 7 is housed in a region where the first spring storage groove 32 and the second storage groove 42 are overlapped in the radial direction. The tension spring 7 is an urging means in the present invention, and the first spring support pin 33 and the second spring support pin 43 are urged in a direction approaching each other in the optical axis direction by the elastic force of the tension spring 7. That is, the first lens cylinder 3 and the second lens cylinder 4 are urged by the tension spring 7 in a direction approaching each other in the optical axis direction.

  The first spring housing groove 32, the second spring housing groove 42, the first spring support pin 33, the second spring support pin 43, and the tension spring 7 are also provided at three locations in the circumferential direction of the lens barrel. However, only one location is shown in FIG.

  In the lens barrel of the first embodiment, as shown in FIG. 3B, the first spring support pin 33 and the first lens barrel 3 are attached to the front side of the lens barrel by the spring force of the tension spring 7. The second spring support pin 43 and the second lens barrel 4 are biased toward the rear side of the lens barrel. Therefore, the first cam pin 31 of the first lens cylinder 3 is brought into contact with the rear inner surface of the first cam groove 21 in the first cam groove 21 of the cam cylinder 2. Further, the second cam pin 41 of the second lens cylinder 4 is brought into contact with the front side inner surface of the second cam groove 22 in the second cam groove 22 of the cam cylinder 2 in a biased state.

  These abutting states are maintained even when the cam cylinder 2 is rotated by the focusing operation as described above and the first cam pin 31 engaged with the first cam groove 21 is moved in the optical axis direction. . Therefore, the first cam pin 31 is always kept in contact with the rear inner surface of the first cam groove 21 by the spring force of the tension spring 7, and there is a backlash between the first cam pin 31 and the first cam groove 21. It does not occur. Similarly, when the second cam pin 42 engaged with the second cam groove 22 is moved in the optical axis direction, the second cam pin 41 is moved inwardly of the front side of the second cam groove 22 by the spring force of the tension spring 7. The state of being in contact with the side surface is maintained, and no play occurs between the second cam pin 41 and the second cam groove 22. As a result, the positions of the first lens unit L1 and the second lens unit L2 in the optical axis direction can be stably prevented from deteriorating the optical performance of the lens barrel, and high focusing accuracy can be obtained.

  The first spring support pin 33, the second spring support pin 43, and the tension spring 7 are stored in the first spring storage groove 32 and the second spring storage groove 42 of the first lens cylinder 3 and the second lens cylinder 4, respectively. It is in the state. In other words, the tension spring 7 is in the radial region of the first lens cylinder 3 and the second lens cylinder 4, that is, the outer peripheral surface of the first lens cylinder 3 on the outer diameter side and the second lens cylinder 4 on the inner diameter side. It is arrange | positioned in the area | region of the radial direction between internal peripheral surfaces. This eliminates the need for a space for arranging the first and second spring support pins 33 and 43 and the tension spring 7 between the first lens cylinder 3 and the second lens cylinder 4. At the same time, there is no need for a space for arranging the first and second spring support pins 33 and 43 and the tension spring 7 in the outer diameter side region of the first lens tube 3 and the inner diameter side region of the second lens tube 4. Become. Thereby, even if the tension spring 7 is housed in the lens barrel, the diameter of the lens barrel is not increased, and the lens barrel can be reduced in diameter.

  In Embodiment 1, the configuration of the present invention can be realized by a total of two spring support pins 33 and 43 erected on the first lens cylinder 3 and the second lens cylinder 4 and one tension spring 7, respectively. 1 is not necessary, the number of parts can be reduced, and the weight of the lens barrel can be reduced by reducing the number of parts.

  FIG. 4 shows a lens barrel of Modification 1 in which a part of Embodiment 1 is modified. FIG. 4 (a) is a plan view similar to FIG. 3 (a) of Embodiment 1, and FIG. FIG. In addition, the same code | symbol is attached | subjected to the part equivalent to FIGS. 1-3. Although not shown in the drawing, the first cam pin 31 of the first lens barrel 3 is disposed on the rear side in the optical axis direction and the second cam pin of the second lens barrel 4 is not shown in the drawing. 41 is arranged on the front side in the optical axis direction. Accordingly, the positions of the first cam groove 21 and the second cam groove 22 of the cam cylinder 2 in the front-rear direction are also reversed. Further, the first cam pin 31 and the second cam pin 41 are disposed at different positions in the circumferential direction.

  In addition, in the first modification, the second spring support pin 43 of the first embodiment is also used as the second cam pin 41. That is, the first spring support pin 33 is erected from the inner diameter direction at a position behind the first spring housing groove 32 of the first lens cylinder 3. The first spring support pin 33 is disposed in the groove of the second spring housing groove 42 of the second lens cylinder 4. The second cam pin 41 is erected on the outer peripheral surface of the second lens cylinder 4 in the first spring housing groove 32 of the first lens cylinder 3, passes through the guide groove 11 of the fixed cylinder 1 and passes through the second cam groove. 22 is engaged.

A tension spring 7 is disposed between the first spring support pin 33 and the second cam pin 41 along the optical axis direction. A front end portion of the tension spring 7 is hooked on the second cam pin 41. The rear end is hooked on the first spring support pin 33. The tension spring 7 is housed in a region where the first spring storage groove 32 and the second storage groove 42 are overlapped in the radial direction.

  According to the first modification, the first lens barrel 3 is urged toward the front side of the lens barrel via the first spring support pin 33 by the spring force of the tension spring 7, and the second lens barrel 4 is the second cam pin. The lens barrel is biased toward the rear side of the lens barrel 41. Therefore, as shown in FIG. 4B, the second cam pin 41 of the second lens cylinder 4 is urged toward the rear inner surface of the second cam groove 22 in the second cam groove 22 of the cam cylinder 2. Abutted in a state. On the contrary, the first cam pin 31 (see FIG. 1) of the first lens barrel 3, not shown in FIG. 4B, is located inside the front side of the first cam groove 21 in the first cam groove 21 of the cam barrel 2. It abuts in a state of being biased to the side surface.

  Therefore, the cam pins 31 and 41 of the first and second lens cylinders 3 and 4 are held in contact with the front or rear inner surface of the cam grooves 21 and 22 by the spring force of the tension spring 7. There is no backlash between the cam pins 31, 41 and the cam grooves 21, 22. As a result, the positions of the first lens unit L1 and the second lens unit L2 in the optical axis direction can be stably prevented from deteriorating the optical performance of the lens barrel, and high focusing accuracy can be obtained.

  In the first modification, the first spring support pin 33 and the tension spring 7 are housed in the first spring housing groove 32 and the second spring housing groove 42 of the first lens cylinder 3 and the second lens cylinder 4, respectively. Therefore, it is disposed in the radial region between the outer peripheral surface of the first lens tube 3 on the outer diameter side and the inner peripheral surface of the second lens tube 4 on the inner diameter side. Accordingly, as in the first embodiment, a space for disposing the tension spring 7 between the first lens cylinder 3 and the second lens cylinder 4 is not necessary, and the outer diameter side region of the first lens cylinder 3 is not necessary. In addition, a space for disposing the tension spring 7 in the inner diameter side region of the second lens cylinder 4 becomes unnecessary. Thereby, even if the tension spring 7 is housed in the lens barrel, the diameter of the lens barrel is not increased, and the lens barrel can be reduced in diameter.

  FIGS. 5A and 5B show a lens barrel of Modification 2 of Embodiment 1 different from Modification 1, and are the same as FIGS. 4A and 4B of Modification 1. FIG. Also in the second modified embodiment, the first cam pin 31 of the first lens cylinder 3 is disposed on the rear side in the optical axis direction, and the second cam pin 41 of the second lens cylinder 4 is disposed on the front side in the optical axis direction. . Accordingly, the positions of the first cam groove 21 and the second cam groove 22 of the cam cylinder 2 in the front-rear direction are also reversed. Further, the first cam pin 31 and the second cam pin 41 are disposed at different positions in the circumferential direction.

  In addition, in the second modification, the first spring housing groove 32 is formed in the first lens cylinder 3 as in the first modification, and the first spring housing groove 32 is a guide formed in the fixed cylinder 1. It is disposed at a position overlapping the groove 11 in the radial direction. On the other hand, the second spring accommodating groove 42 in the first embodiment is not formed in the second lens cylinder 4.

  In the second modified example, the second spring support pin is also used as the second cam pin 41. That is, the first spring support pin 33 is erected on the outer peripheral surface of the rear position of the first spring housing groove 32 of the first lens barrel 3 from the outer diameter direction. The first spring support pin 33 is disposed in the groove of the guide groove 11 of the fixed cylinder 1. A tension spring 7 is disposed between the first spring support pin 33 and the second cam pin 41 along the optical axis direction. A front end portion of the tension spring 7 is hooked on the second cam pin 41. The rear end is hooked on the first spring support pin 33. The tension spring 7 is provided in a region where the guide groove 11 of the fixed cylinder 1 and the first spring storage groove 32 of the first lens cylinder 3 are overlapped in the radial direction.

  According to the second modification, as in the first modification, the first lens barrel 3 is urged toward the front side of the lens barrel via the first spring support pin 33 by the spring force of the tension spring 7, and the second The lens barrel 4 is urged toward the rear side of the lens barrel via the second cam pin 41. Therefore, as shown in FIG. 5B, the second cam pin 41 of the second lens cylinder 4 is urged toward the rear inner surface of the second cam groove 22 in the second cam groove 22 of the cam cylinder. Is abutted. The first cam pin 31 (see FIG. 1) of the first lens barrel 3 that does not appear in FIG. 5B is biased to the front inner surface of the first cam groove 21 in the first cam groove 21 of the cam barrel 2. It contacts in the state where it was done.

  Accordingly, the cam pins 31 and 41 of the first lens cylinder 3 and the second lens cylinder 4 are maintained in contact with the front or rear inner surfaces of the cam grooves 21 and 22 by the spring force of the tension spring 7. There is no backlash between the cam pins 31, 41 and the cam grooves 21, 22. As a result, the positions of the first lens unit L1 and the second lens unit L2 in the optical axis direction can be stably prevented from deteriorating the optical performance of the lens barrel, and high focusing accuracy can be obtained.

  In the second modification, the tension spring 7 is accommodated in the guide groove 11 of the fixed cylinder 1 and the first spring accommodation groove 32 of the first lens cylinder 3. In other words, it is disposed in a radial region between the outer peripheral surface of the fixed tube 1 on the outer diameter side and the inner peripheral surface of the first lens tube 3 on the inner diameter side. Thereby, a space for disposing the tension spring 7 between the fixed cylinder 1 and the first lens cylinder 3 is not necessary, and the outer diameter side area of the fixed cylinder 1 and the inner diameter side area of the first lens cylinder 3 are not required. In addition, a space for disposing the tension spring 7 becomes unnecessary. Thereby, even if the tension spring 7 is housed in the lens barrel, the diameter of the lens barrel is not increased, and the lens barrel can be reduced in diameter.

  Here, in these modifications 1 and 2, the other end of the tension spring, that is, the rear end portion of the tension spring may be hooked on the first cam pin of the first lens cylinder. 6A and 6B show a third modification of the first embodiment, which is the same as FIGS. 5A and 5B. In the third modification, both ends of the tension spring 7 are hooked on the first cam pin 31 and the second cam pin 41. The tension spring 7 is disposed in the region of the guide groove 11 of the fixed cylinder 1 and the first spring storage groove 32 of the first lens cylinder 3.

  Also in the third modification, the first lens cylinder 3 and the second lens cylinder 4 can be urged in the optical axis direction by the tension spring 7, and the first and second cam pins 31, 41, the first and first No play occurs between the two cam grooves 21 and 22, the positions of the first lens unit L1 and the second lens unit L2 in the optical axis direction are stable, and the optical performance of the lens barrel can be prevented from deteriorating. High focusing accuracy can be obtained.

  Similarly to the second modification, the tension spring 7 is housed in the guide groove 11 of the fixed tube 1 and the first spring housing groove 32 of the first lens tube 3, and the fixed tube 1, the first lens tube 3, and the like. There is no need for a space for disposing the tension spring 7 between them, and there is also a space for disposing the tension spring 7 in the outer diameter side region of the fixed tube 1 and the inner diameter side region of the first lens tube 3. It becomes unnecessary. Thereby, even if the tension spring 7 is housed in the lens barrel, the diameter of the lens barrel is not increased, and the lens barrel can be reduced in diameter. Furthermore, the first spring support pin 33 in the first lens cylinder 3 and the second spring support pin 43 in the second lens cylinder 4 are not necessary, and the configuration can be further simplified.

  FIG. 7 shows the lens barrel of the second embodiment, which is the same as FIGS. 3A and 3B of the first embodiment. Parts equivalent to those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. In the second embodiment, the urging means of the present invention is constituted by a leaf spring.

  The first and second lens barrels 3 and 4 are formed with the first spring accommodating groove 32 and the second spring accommodating groove 42 that are partially overlapped in the radial direction in the optical axis direction, as in the first embodiment. However, the first spring support pin is not provided, and the second spring support pin 43 is located at the front end position of the second spring storage groove 42 on the outer peripheral surface of the second lens tube 4 and in the first spring storage groove 32. It stands upright in the groove. The second spring support pin 43 is fixedly supported by a base end portion of a leaf spring 7A that is housed in the region of the first spring storage groove 32 and the second spring storage groove 42. The tip of the leaf spring 7A is bent so as to protrude rearward and is elastically contacted with the inner surface of the rear end of the first spring housing groove 32 in the optical axis direction.

  The plate spring 7A has at least a region including the tip that can be elastically deformed in the plate thickness direction. The first spring housing groove 32 is in contact with the tip by a spring force generated when the plate spring 7A is bent. A rearward biasing force is applied to the inner surface of the rear end. As a result, the first lens cylinder 3 is urged rearward. Further, the second spring support pin 43 supporting the leaf spring 7A, that is, the second lens tube 4 is moved in the front direction by the reaction force when the leaf spring 7A biases the first lens tube 3 in the rearward direction. Be energized by. These urging directions are opposite to those in the first embodiment.

  In the second embodiment, the first lens cylinder 3 is urged toward the rear side of the lens barrel and the second lens cylinder 4 is urged toward the front side of the lens barrel by the spring force of the leaf spring 7A. In the cam cylinder 2 (described in the first embodiment), the first cam pin 31 of the first lens cylinder 3 is brought into contact with the rear inner surface in the first cam groove 21 of the cam cylinder in a biased state. On the contrary, the second cam pin 41 of the second lens barrel 4 is brought into contact with the front inner surface of the second cam groove 22 of the cam barrel 2 while being urged.

  This state is maintained even when the cam cylinder 2 is rotated by the focusing operation, and the first lens cylinder 3 and the second lens cylinder 4 are moved in the optical axis direction by the rotation of the cam cylinder 2. As a result, no play occurs between the first cam pin 31 and the first cam groove 21 and between the second cam pin 41 and the second cam groove 22, and the first lens group L1 and the second lens group L2. Thus, the position in the optical axis direction can be stably prevented from deteriorating the optical performance of the lens barrel, and high focusing accuracy can be obtained.

  The second spring support pin 43 and the leaf spring 7A are in a state of being housed in the first spring housing groove 32 and the second spring housing groove 42. That is, in the same manner as in the first embodiment, in the radial region of the first lens cylinder 3 and the second lens cylinder 4, in other words, the outer peripheral surface of the first lens cylinder 3 on the outer diameter side, and the second lens cylinder on the inner diameter side. 4 is disposed in a radial region between the inner peripheral surface of the four. Thereby, a space for disposing the leaf spring 7A between the first lens cylinder 3 and the second lens cylinder 4 is not necessary, and the outer diameter side region of the first lens cylinder 3 and the second lens cylinder 4 are disposed. No space for disposing the leaf spring 7A is required in the inner diameter side region. As a result, the diameter of the lens barrel is not increased, and the diameter of the lens barrel can be reduced.

  In the second embodiment, the present invention can be configured with one spring support pin 43 erected on the second lens cylinder 4 and one leaf spring 7A. The number of parts can be reduced and the weight of the lens barrel can be reduced by reducing the number of parts. Further, since the spring support pin 43 and the leaf spring 7A can be disposed from the outer diameter side of the first lens barrel 3, the assembling work of the lens barrel is easy.

  FIG. 8 shows the lens barrel of the third embodiment, which is the same as FIGS. 3A and 3B of the first embodiment. Portions equivalent to those in the first and second embodiments are denoted by the same reference numerals, and redundant description is omitted. In the third embodiment, the biasing means of the present invention is constituted by a torsion spring.

  The first spring storage groove 32 is formed in the first lens cylinder 3 and the second spring storage groove 42 is not formed in the second lens cylinder 4 as in the second embodiment. The second spring support pin 43 is erected on the outer peripheral surface of the second lens cylinder 4 in the groove of the first spring housing groove 32. A fulcrum portion of a torsion spring 7B housed in the second spring housing groove 32 is fixedly supported on the second spring support pin 43. One end of the torsion spring 7B is hooked on a step 44 provided on a part of the outer peripheral surface of the second lens cylinder 4, and the other end is elastically contacted with the inner surface of the rear end of the first spring housing groove 32. ing.

  The torsion spring 7B applies a rearward biasing force to the inner surface of the rear end of the first spring housing groove 32 that is elastically contacted with the other end by a spring force generated when both ends are elastically deformed in the direction in which both ends approach each other. Added. As a result, the first lens cylinder 3 is urged rearward. Further, since one end of the torsion spring 7B is hooked on the step portion 44 of the second lens cylinder 4, the second lens cylinder 4 is biased in the front direction. These urging directions are the same as those in the second embodiment.

  In the third embodiment, the first lens cylinder 3 is urged toward the rear side of the lens barrel and the second lens cylinder 4 is urged toward the front side of the lens barrel by the spring force of the torsion spring 7B. . Therefore, in the cam cylinder 2 (described in the first embodiment), the first cam pin 31 of the first lens cylinder 3 is brought into contact with the rear inner surface of the first cam groove 21 while being urged. The second cam pin 41 of the lens tube 4 is brought into contact with the front inner surface of the second cam groove 22 in a biased state.

  This state is maintained even when the cam cylinder 2 is rotated by a focusing operation, so that the state is between the first cam pin 31 and the first cam groove 21 and between the second cam pin 41 and the second cam groove 22. There will be no backlash. As a result, the positions of the first lens unit L1 and the second lens unit L2 in the optical axis direction can be stably prevented from deteriorating the optical performance of the lens barrel, and high focusing accuracy can be obtained.

  The second spring support pin 43 and the torsion spring 7 </ b> B are in a state of being housed in the first spring housing groove 32. That is, as in the first and second embodiments, it is disposed in a radial region between the outer peripheral surface of the first lens tube 3 on the outer diameter side and the inner peripheral surface of the second lens tube 4 on the inner diameter side. ing. Thereby, a space for disposing the torsion spring 7B between the first lens cylinder 3 and the second lens cylinder 4 is unnecessary, and the outer diameter side region of the first lens cylinder 3 and the second lens are disposed. A space for disposing the torsion spring 7B in the inner diameter side region of the cylinder 4 is not necessary. As a result, the diameter of the lens barrel is not increased, and the diameter of the lens barrel can be reduced.

  In the third embodiment, the present invention can be configured by one spring support pin 43 erected on the second lens cylinder 4 and one torsion spring 7B. In addition, the number of parts can be reduced and the weight of the lens barrel can be reduced by reducing the number of parts. Further, since the spring support pin and the torsion spring can be disposed only from the outer diameter side of the first lens barrel, the assembling work of the lens barrel is easy.

  In each of the above-described embodiments and modifications, an example in which the present invention is applied to a lens barrel focusing mechanism has been described. However, the focal length is changed by moving the lens group and the lens barrel in the optical axis direction by a zooming operation. It is also possible to apply to a zooming mechanism.

  In each of the above-described embodiments and modifications, an example in which the present invention is applied to a lens barrel that includes a fixed barrel that is built in a lens barrel and a first lens barrel and a second lens barrel as moving members has been shown. The present invention can also be applied to one moving member that is moved relative to the fixed member, that is, a lens barrel that includes a lens barrel. Or it is applicable also to a lens barrel provided with three or more moving members, that is, three or more lens tubes. In this case, an urging member may be disposed between a pair of lens barrels in which three lens barrels are appropriately combined.

  In the present invention, when the biasing means is disposed in the radial region of the fixed cylinder and the moving member, the biasing means may be disposed in each region of the fixed cylinder and the moving member adjacent to the radial direction. In the case where the second moving member is adjacent to the fixed cylinder in the radial direction, the urging means may be disposed in the area of the fixed cylinder and the second moving member.

  In the embodiment and the modification described above, the lens barrel that moves the moving member in the optical axis direction by the cam mechanism is applied. However, when the moving member is moved in the optical axis direction, a mechanism that causes backlash or the like is generated. If so, it can also be applied to a lens barrel that employs a mechanism that is moved by a lead screw mechanism, a lever mechanism, or a link mechanism.

  The moving member in the present invention is not limited to the lens barrel, and can be applied to optical elements other than the lens barrel that is mounted in the lens barrel and moves in the optical axis direction. The biasing means in the present invention is not limited to the tension spring, the leaf spring, and the torsion spring described in the embodiment, and any means that biases in the optical axis direction can be applied. For example, it may be a compression coil spring, an accordion-like leaf spring in which a leaf spring material is bent into a waveform.

  The spring storage groove described in the embodiment and the modification may not be formed as an opening groove penetrating in the radial direction of the moving member, and is recessed in the radial direction as long as the biasing means can be stored. It may be a recessed groove provided.

  The present invention can be applied to an optical apparatus including the lens barrel described in each embodiment. For example, the present invention can be applied to an optical device including a lens barrel integrated with an imaging device such as a camera, a replacement lens barrel of the imaging device, a lens barrel of a telescope or binoculars, or a lens barrel of a projector.

DESCRIPTION OF SYMBOLS 1 Fixed cylinder 2 Cam cylinder 3 1st lens cylinder (1st moving member)
4 Second lens tube (second moving member)
5 First lens frame (first moving member)
6 Second lens frame (second moving member)
7 Tension spring (biasing means)
7A leaf spring (biasing means)
7B Torsion spring (biasing means)
11 Guide groove 21 1st cam groove 22 2nd cam groove 31 1st cam pin 32 1st spring accommodation groove 33 1st spring support pin 41 2nd cam pin 42 2nd spring accommodation groove 43 2nd spring support pin

Claims (12)

  A lens barrel that includes a first moving member and a second moving member that are disposed so as to overlap in the radial direction of the lens barrel and that are moved in the optical axis direction of the lens barrel, the first moving member and An urging means is provided between the second moving member and urges both members in the optical axis direction. The urging means includes the first moving member and the second moving member. A lens barrel characterized by being disposed in a radial region.   A fixed barrel of the lens barrel, and a first moving member and a second moving member which are disposed so as to overlap the fixed barrel in the radial direction of the lens barrel and which are moved in the optical axis direction of the lens barrel. A lens barrel including biasing means that is interposed between the first moving member and the second moving member and biases both members in the optical axis direction. A lens barrel, wherein the lens barrel is disposed in a radial region in which a fixed cylinder and a moving member adjacent to the fixed cylinder among the first moving member and the second moving member are present.     At least one of the first moving member and the second moving member is formed with a storage groove formed of a radial opening groove or a concave groove extending in the optical axis direction, and the biasing means is formed in the storage groove. The lens barrel according to claim 1 or 2, wherein the lens barrel is housed.   The lens barrel according to claim 3, wherein the biasing means is a coil spring having one end hooked to the first moving member and the other end hooked to the second moving member.   The lens barrel according to claim 4, wherein one end of the coil spring is hooked on a cam pin of the first moving member or the second moving member.   The urging means is a leaf spring or a torsion that is fixedly supported by one moving member of the first moving member or the second moving member and whose elastically deformable end is in contact with the other moving member. The lens barrel according to claim 3, wherein the lens barrel is a spring.   The lens barrel includes a cam barrel that has a cam groove and is rotated. The first moving member and the second moving member include a cam pin that is cam-engaged with the cam groove. The lens barrel according to claim 1, wherein the first moving member and the second moving member are moved in the optical axis direction by rotation.   A cam cylinder that is rotated, a first lens cylinder that supports the first lens group that is cam-engaged and moved in the optical axis direction, and a cam-engaged cam that engages the first lens. A second lens cylinder that supports a second lens group that is moved in the optical axis direction independently of the cylinder; and is interposed between the first lens cylinder and the second lens cylinder to light both lens cylinders. A lens barrel comprising biasing means for biasing in the axial direction, wherein a storage groove for storing the biasing means is formed in at least one of the first lens cylinder and the second lens cylinder.   The lens barrel further includes a fixed cylinder, and a storage groove for storing the biasing means is formed in a lens cylinder that is radially adjacent to the fixed cylinder among the first lens cylinder and the second lens cylinder. The lens barrel according to claim 8.   10. The lens barrel according to claim 8, wherein storage grooves communicating with each other are formed in each of the first lens cylinder and the second lens cylinder, and the urging means is stored over these storage grooves.   The lens barrel according to claim 9 or 10, wherein the fixed cylinder includes a storage groove communicated with the storage groove, and the urging unit is stored over the storage grooves. An optical apparatus comprising the lens barrel according to any one of claims 1 to 11.

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